Die-casting machine



Jan, 1, 1935. H. 'rl-HEUER` DIE CASTING MACHINE Filed oct. 6, 1931 Patented Jan. l., u i935 @ENCE DIE-CASTENG MA mar- Hans Theuer, cologne-raunsfeld, Germany, aasignor to Eckert & Ziegler G. m. b. H., Cologne- Braunsfeld, Germany, a corporation of Germany October 8, 1930 11 Claims.

My invention relates to' improvements in diecasting machines,. and more particularly in the construction of the cylinder and piston for forcing the molten material into the moulds, which cylinder is formed with an annular cavity receiving the material and means for heating the said material within the cylinder. The object of the improvements is to provide a cylinder and piston by means of which the material is rapidly and uniformly molten by being heated from the outer and inner side of the annular cavity, and which permits the molten material to be delivered under high pressure. With this object in view my invention consists in forming the annular cavity within the cylinder by means of ai solidcylindrical core pressed into the cylinder, the cylinder being provided with outer heating rmeans and in addition a heating device being disposed within the said bore of the cylindrical core. Thereby the wall of the cylinder may be made so strong that it is able to take up the high pressure exerted on the molten material, which pressure is, in modern machines, as high as from 40 to 60 atmospheres. Notwithstanding the thick wall of the cylinder the transmission' of` heat to the material is not interfered with. Further, the apparatus takes little room, so that very small castingsmay be manufactured.

Preferably the solid core disposed within the cylinder is mounted so that it may be readily exchanged, which is important for the reason that a single cylinder may be used in connection with moulds of various forms, the solid core being adapted to the said moulds. 35l For the purpose of explaining theinvention an example embodying the same has been shown in the accompanying drawing in which the same reference characters have been used in all thev views to indicate corresponding parts. In said thawing,

Fig. v1 is a sectional elevation showing the cylinder and its piston,

Fig. 2` is a sectional elevation takenon the line 2-2 of Fla. 1. and A Fig. 3 is a fragmentary elevation showing the head of the core and the nozzles fixedY thereto.

In the example shown inthe figures the apparatus comprises a cylinder a having asolid 4core d mounted therein, the diameter of the said core being smaller than the inner diameter "of the cylinder so as to provide an annular chamber, c. The core is formed with an enlarged cylindrical head t iltting in the bore of the cylinder'and with a ange t fitting in an lannular 55 recess of the cylinder. Within the cylinder -an annular piston m has reciprocating movement, which' piston encloses the core d. Suitable means are provided for imparting reciprocating movement to the piston m. But such means do not form a part of my invention, and therefore they 5 have not been illustrated in the figures. In the operation of the piston m the air is admitted to or delivered from the piston througha vent r.

The cylinder is mounted in a cross-head h and it is xed in position by means of a nut k. The l0 said cross-head h carries a tunnel i which is connected withathe rear part of the annular 'chamber e by means of holes u made in the cross-head h and the cylinder a.

In screw-threaded sockets f of the head t of l5 the core nozzles g are screwed the bores n of which are connected with the annular chamber c. When forcing the piston m inwardly the material is forced from the annular chamber into the bores n of the nozzles g, and in order to 'have a smooth 20 transmission of the molten material and to :educe the resistance of the flow of the material, the head t is formed with triangular notches p, the side walls q of which guide the molten material from the annular chamber c to the nozzles. 25 Thereby the material is prevented from being collected on the end wall of the chamber Dc provided by the head t, which would be objectionable for the reason that the material would be exposed to excessive heat and burnt and carried `30 away into the moulds, where it would spoil the castings.

The core d may be readily removed from the i cylinder `a and replaced bya core of another form the nozzles of which are adapted to another mould. 'I'hus the saine cylinder may be usedin connection with moulds of diilerent form.

The cylinder is heated by external heating means b. In addition the core d is formed with an axial bore u in which-a heating device e is lo- 40 cated. As shown, both heating means b and e arev in `the form of electrical resistance-wires. Preferably, separate leading-in wires are `provided for both resistances b and e by means of which the currents supplied to the resistances may be separately regulated. I have found that there. by exact regulation of the temperature of the material may be obtained, and the material may be rapidly heated and moltenwith a minimum of electrical energy. 'Ihe apparatus may be oper- 50 ated at high velocity, and its eiiiciencykand economy are high. @In the operation of the apparatus the cylinder y is placed with its nozzles g into position for ysquirting the molten material into the mould, the

2 f number'of the said nozzles corresponding to the` -number of the intakes of the mould, the material is filled into the chamber c through the funnel i, the material is molten by means of the resistances b and e, and finally, the piston m Vis forced inwardly and into the chamber c. Thereby the molten material is delivered through the nozzles y, and by reason of the triangular notches p formed in the head t the material is smoothly delivered from the chamber c to the nozzles g, and there is no possibility of any material being arrested in front ofthe head t.

The apparatus disclosed above is designed to be used for the manufacture of mass articles con- `sisting of artificial substances by way of example and not in a limiting sense. It is adaptable for working upon acetyl cellulose derivates, polymer` ized styrol, etc. etc. The apparatus is not designed for casting metals. a f

I claim:

` 1. A mass cylinder for die-casting machines for forcing molten artificial plastic material to the mold comprising a cylinder capable of withstanding the high `pressures used in die-casting machines, a core member also capable. of withstanding the high pressures indie-casting machines located within said-cylinder and spaced therefrom to form an annular chamber, means for feeding the material to d annular `chamber, an annular .piston reciprocating vwithin said annular chamber, means for heating said core and means for directing the heated material from said annular chamber to a mold.

2. A mass cylinder for die-casting machines for forcing molten artificial plastic material to the mold comprising a cylinder capable of withstanding the high pressures used in die-casting machines, a core member also capable of withstanding the high lpressures in die-casting machines located within said cylinder and spaced therefrom to form an annular chamber, means for feeding 'material to said annular chamber, an annular piston reciprocating within said annular chamber, said core having a longitudinal bore therein, heating means located,- within said bore and means for directingthe heated material fchines located within said cylinder and-spaced therefrom to form an annular chamber, means for feeding the material to said annular chamber, an annular piston reciprocating within said annular chamber,` means .for heating said core and a nozzle mounted upon said core for directing the heated material from said annular chamber to a 4. A mass cylinder for die-casting machines for forcingmolten artici'al plastic material to they mold comprising a cylinder capable' of withstanding the high pressures used in die-casting Y machines, a core member also capable of withwithin said annular chamber, means for heating said removable core and m; 'for directing the heated material frojm said :u ular chamber to `a 5. A mass cylinder for die-casting machines for forcing molten artificial plastic material to the mold comprising a supporting member, a cylinder capable of withstanding high pressures used in die-casting machines mounted upon said 'supporting member, a core membery also capable of withstanding the high pressures in die-casting machines located within said cylinder and spaced therefrom to'form an annular chamber, means upon said supporting member for feeding material to said annular chamber, an annular piston reciprocating within said annular chamber, means for heating said core and means for directing the heated material from said annular chamber to a mold.

6. A mass cylinder for die-casting machines for forcing molten artificial plastic material to the mold comprising a cylinder capable of withstanding the high pressures used in die-casting machines, a core member also capable of withstanding the high pressures in die-casting machines located within said cylinder and spaced therefrom-to form an annular chamber, van annular -piston reciprocating within said annular chamber, means for heating Asaid core, a nozzle communicating with said annular chamber through Awhich the material is directed to a 'mold and a standingv the high pressures in die-casting machines located within said cylinder and spaced therefrom to form an annular chamber, means for feeding material to said annular chamber, an annular piston reciprocating within said annular chamberfmeans for heating said core, said core having at its outer ends a head fitting in said cylinder, said head having notches tapering from said annular chamber outwardly and nozzles on said head having communication with the'passages formed by said nozzles.

8. A mass cylinder for die-casting machines for forcing molten artificial plastic material to the m'old comprising a cylinder capable of withstanding the high pressures used in die-casting machines, a. core member also capable of withstanding the high pressures used in die-casting machines located with said cylinder and spaced therefrom to form an annular chamber, an annular piston reciprocating Within said annular chamber, means for heating 'said core throughout. a substantial proportion of its longitudinal lengtln means for feeding material to said annularchamber and a plurality of no es having communication withsaid annular hamber for directing the heated material to molds.

9. A mass cylinder for die-casting machines 'for forcing molten artificial plastic materilto the mold comprising a supporting member, a cylin- .der capable of withstanding the high pressures used inv die-casting machines supported at one end by said supporting member, a core member also capable of withstanding the high pressures in die-casting machines located within said cylinder and spaced therefrom to form an annular chamber, a. head integral with said core fitting into the other end of said cylinder, nozzles upon said head having communication with said annular chamber, means for heating said core throughout a substantialportion of 4Iits longitudin al length and an annular piston reciprocating in said annular chamber. l

10. A mass cylinder for die-casting machines for forcing molten articial plastic material to the mold comprising a'supporting member, a cylinder capable of withstanding the high pressures used in die-casting machines supported at one end by said supporting member, a core'member also capable of withstanding the high pressures in die-casting machines located within said cylinder and spaced therefrom to form an annular chamber, a head integral with said core fitting into the other end of said cylinder, nozzles upon said head having communication with said annular cham-l Vbergmeans for heating said core throughout a substantial portion oi its longitudinal length,'an annular piston reciprocating in said annular chamber and an air vent in said annular piston 'permitting the same to reciprocate-freely;

11. A mass cylinder for die-casting machines I for forcing molten artificial plastic material to the mold comprising a cylinder capable of with-A standing the high pressures used in die-casting machines, a core member also capable 'of withstanding the high pressures in die-casting machines located within saidcylinder and spaced therefrom to `form an annular chamber, means for feeding the material to said annular chamber,

an annular piston reciprocating within said annular chamber, means for heating said core throughout a substantial portion of its longitudinal length, means for heating said cylinder and means for directing the heated material from said annular chamber to a mold. HANS THEUER. 

